package com.dbh.company.util;

import java.util.Arrays;

/**
 * 
 * A very fast and memory efficient class to encode and decode to and from
 * 
 * BASE64 in full accordance with RFC 2045.<br>
 * 
 * <br>
 * 
 * On Windows XP sp1 with 1.4.2_04 and later ;), this encoder and decoder is
 * 
 * about 10 times faster on small arrays (10 - 1000 bytes) and 2-3 times as fast
 * 
 * on larger arrays (10000 - 1000000 bytes) compared to
 * 
 * <code>sun.misc.Encoder()/Decoder()</code>.<br>
 * 
 * <br>
 * 
 * 
 * 
 * On byte arrays the encoder is about 20% faster than Jakarta Commons Base64
 * 
 * Codec for encode and about 50% faster for decoding large arrays. This
 * 
 * implementation is about twice as fast on very small arrays (< 30 bytes). If
 * 
 * source/destination is a <code>String</code> this version is about three
 * 
 * times as fast due to the fact that the Commons Codec result has to be recoded
 * 
 * to a <code>String</code> from <code>byte[]</code>, which is very
 * 
 * expensive.<br>
 * 
 * <br>
 * 
 * 
 * 
 * This encode/decode algorithm doesn't create any temporary arrays as many
 * 
 * other codecs do, it only allocates the resulting array. This produces less
 * 
 * garbage and it is possible to handle arrays twice as large as algorithms that
 * 
 * create a temporary array. (E.g. Jakarta Commons Codec). It is unknown whether
 * 
 * Sun's <code>sun.misc.Encoder()/Decoder()</code> produce temporary arrays
 * 
 * but since performance is quite low it probably does.<br>
 * 
 * <br>
 * 
 * 
 * 
 * The encoder produces the same output as the Sun one except that the Sun's
 * 
 * encoder appends a trailing line separator if the last character isn't a pad.
 * 
 * Unclear why but it only adds to the length and is probably a side effect.
 * 
 * Both are in conformance with RFC 2045 though.<br>
 * 
 * Commons codec seem to always att a trailing line separator.<br>
 * 
 * <br>
 * 
 * 
 * 
 * <b>Note!</b> The encode/decode method pairs (types) come in three versions
 * 
 * with the <b>exact</b> same algorithm and thus a lot of code redundancy. This
 * 
 * is to not create any temporary arrays for transcoding to/from different
 * 
 * format types. The methods not used can simply be commented out.<br>
 * 
 * <br>
 * 
 * 
 * 
 * There is also a "fast" version of all decode methods that works the same way
 * 
 * as the normal ones, but har a few demands on the decoded input. Normally
 * 
 * though, these fast verions should be used if the source if the input is known
 * 
 * and it hasn't bee tampered with.<br>
 * 
 * <br>
 * 
 * 
 * 
 * If you find the code useful or you find a bug, please send me a note at
 * 
 * base64 @ miginfocom . com.
 * 
 * 
 * 
 * Licence (BSD): ==============
 * 
 * 
 * 
 * Copyright (c) 2004, Mikael Grev, MiG InfoCom AB. (base64 @ miginfocom . com)
 * 
 * All rights reserved.
 * 
 * 
 * 
 * Redistribution and use in source and binary forms, with or without
 * 
 * modification, are permitted provided that the following conditions are met:
 * 
 * Redistributions of source code must retain the above copyright notice, this
 * 
 * list of conditions and the following disclaimer. Redistributions in binary
 * 
 * form must reproduce the above copyright notice, this list of conditions and
 * 
 * the following disclaimer in the documentation and/or other materials provided
 * 
 * with the distribution. Neither the name of the MiG InfoCom AB nor the names
 * 
 * of its contributors may be used to endorse or promote products derived from
 * 
 * this software without specific prior written permission.
 * 
 * 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * 
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * 
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * 
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * 
 * 
 * @version 2.2
 * 
 * @author Mikael Grev Date: 2004-aug-02 Time: 11:31:11
 * 
 */

public class Base64 {

	private static final boolean devLineSep = true;

	private static final char[] CA = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

	.toCharArray();

	private static final int[] IA = new int[256];

	static {

		Arrays.fill(IA, -1);

		for (int i = 0, iS = CA.length; i < iS; i++)

			IA[CA[i]] = i;

		IA['='] = 0;

	}

	// ****************************************************************************************

	// * char[] version

	// ****************************************************************************************

	public final static char[] encodeToChar(byte[] sArr) {

		return encodeToChar(sArr, devLineSep);

	}

	/**
	 * 
	 * Encodes a raw byte array into a BASE64 <code>char[]</code>
	 * 
	 * representation i accordance with RFC 2045.
	 * 
	 * 
	 * 
	 * @param sArr
	 * 
	 * The bytes to convert. If <code>null</code> or length 0 an
	 * 
	 * empty array will be returned.
	 * 
	 * @param lineSep
	 * 
	 * Optional "\r\n" after 76 characters, unless end of file.<br>
	 * 
	 * No line separator will be in breach of RFC 2045 which
	 * 
	 * specifies max 76 per line but will be a little faster.
	 * 
	 * @return A BASE64 encoded array. Never <code>null</code>.
	 * 
	 */

	public final static char[] encodeToChar(byte[] sArr, boolean lineSep) {

		// Check special case

		int sLen = sArr != null ? sArr.length : 0;

		if (sLen == 0)

			return new char[0];

		int eLen = (sLen / 3) * 3; // Length of even 24-bits.

		int cCnt = ((sLen - 1) / 3 + 1) << 2; // Returned character count

		int dLen = cCnt + (lineSep ? (cCnt - 1) / 76 << 1 : 0); // Length of

		// returned

		// array

		char[] dArr = new char[dLen];

		// Encode even 24-bits

		for (int s = 0, d = 0, cc = 0; s < eLen;) {

			// Copy next three bytes into lower 24 bits of int, paying attension

			// to sign.

			int i = (sArr[s++] & 0xff) << 16 | (sArr[s++] & 0xff) << 8

			| (sArr[s++] & 0xff);

			// Encode the int into four chars

			dArr[d++] = CA[(i >>> 18) & 0x3f];

			dArr[d++] = CA[(i >>> 12) & 0x3f];

			dArr[d++] = CA[(i >>> 6) & 0x3f];

			dArr[d++] = CA[i & 0x3f];

			// Add optional line separator

			if (lineSep && ++cc == 19 && d < dLen - 2) {

				dArr[d++] = '\r';

				dArr[d++] = '\n';

				cc = 0;

			}

		}

		// Pad and encode last bits if source isn't even 24 bits.

		int left = sLen - eLen; // 0 - 2.

		if (left > 0) {

			// Prepare the int

			int i = ((sArr[eLen] & 0xff) << 10)

			| (left == 2 ? ((sArr[sLen - 1] & 0xff) << 2) : 0);

			// Set last four chars

			dArr[dLen - 4] = CA[i >> 12];

			dArr[dLen - 3] = CA[(i >>> 6) & 0x3f];

			dArr[dLen - 2] = left == 2 ? CA[i & 0x3f] : '=';

			dArr[dLen - 1] = '=';

		}

		return dArr;

	}

	/**
	 * 
	 * Decodes a BASE64 encoded char array. All illegal characters will be
	 * 
	 * ignored and can handle both arrays with and without line separators.
	 * 
	 * 
	 * 
	 * @param sArr
	 * 
	 * The source array. <code>null</code> or length 0 will return
	 * 
	 * an empty array.
	 * 
	 * @return The decoded array of bytes. May be of length 0. Will be
	 * 
	 * <code>null</code> if the legal characters (including '=') isn't
	 * 
	 * divideable by 4. (I.e. definitely corrupted).
	 * 
	 */

	public final static byte[] decode(char[] sArr) {

		// Check special case

		int sLen = sArr != null ? sArr.length : 0;

		if (sLen == 0)

			return new byte[0];

		// Count illegal characters (including '\r', '\n') to know what size the

		// returned array will be,

		// so we don't have to reallocate & copy it later.

		int sepCnt = 0; // Number of separator characters. (Actually illegal

		// characters, but that's a bonus...)

		for (int i = 0; i < sLen; i++)

			// If input is "pure" (I.e. no line separators or illegal chars)

			// base64 this loop can be commented out.

			if (IA[sArr[i]] < 0)

				sepCnt++;

		// Check so that legal chars (including '=') are evenly divideable by 4

		// as specified in RFC 2045.

		if ((sLen - sepCnt) % 4 != 0)

			return null;

		int pad = 0;

		for (int i = sLen; i > 1 && IA[sArr[--i]] <= 0;)

			if (sArr[i] == '=')

				pad++;

		int len = ((sLen - sepCnt) * 6 >> 3) - pad;

		byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

		for (int s = 0, d = 0; d < len;) {

			// Assemble three bytes into an int from four "valid" characters.

			int i = 0;

			for (int j = 0; j < 4; j++) { // j only increased if a valid char

				// was found.

				int c = IA[sArr[s++]];

				if (c >= 0)

					i |= c << (18 - j * 6);

				else

					j--;

			}

			// Add the bytes

			dArr[d++] = (byte) (i >> 16);

			if (d < len) {

				dArr[d++] = (byte) (i >> 8);

				if (d < len)

					dArr[d++] = (byte) i;

			}

		}

		return dArr;

	}

	/**
	 * 
	 * Decodes a BASE64 encoded char array that is known to be resonably well
	 * 
	 * formatted. The method is about twice as fast as {@link #decode(char[])}.
	 * 
	 * The preconditions are:<br> + The array must have a line length of 76
	 * 
	 * chars OR no line separators at all (one line).<br> + Line separator must
	 * 
	 * be "\r\n", as specified in RFC 2045 + The array must not contain illegal
	 * 
	 * characters within the encoded string<br> + The array CAN have illegal
	 * 
	 * characters at the beginning and end, those will be dealt with
	 * 
	 * appropriately.<br>
	 * 
	 * 
	 * 
	 * @param sArr
	 * 
	 * The source array. Length 0 will return an empty array.
	 * 
	 * <code>null</code> will throw an exception.
	 * 
	 * @return The decoded array of bytes. May be of length 0.
	 * 
	 */

	public final static byte[] decodeFast(char[] sArr) {

		// Check special case

		int sLen = sArr.length;

		if (sLen == 0)

			return new byte[0];

		int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.

		// Trim illegal chars from start

		while (sIx < eIx && IA[sArr[sIx]] < 0)

			sIx++;

		// Trim illegal chars from end

		while (eIx > 0 && IA[sArr[eIx]] < 0)

			eIx--;

		// get the padding count (=) (0, 1 or 2)

		int pad = sArr[eIx] == '=' ? (sArr[eIx - 1] == '=' ? 2 : 1) : 0; // Count

		// '='

		// at

		// end.

		int cCnt = eIx - sIx + 1; // Content count including possible

		// separators

		int sepCnt = sLen > 76 ? (sArr[76] == '\r' ? cCnt / 78 : 0) << 1 : 0;

		int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

		// bytes

		byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

		// Decode all but the last 0 - 2 bytes.

		int d = 0;

		for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

			// Assemble three bytes into an int from four "valid" characters.

			int i = IA[sArr[sIx++]] << 18 | IA[sArr[sIx++]] << 12

			| IA[sArr[sIx++]] << 6 | IA[sArr[sIx++]];

			// Add the bytes

			dArr[d++] = (byte) (i >> 16);

			dArr[d++] = (byte) (i >> 8);

			dArr[d++] = (byte) i;

			// If line separator, jump over it.

			if (sepCnt > 0 && ++cc == 19) {

				sIx += 2;

				cc = 0;

			}

		}

		if (d < len) {

			// Decode last 1-3 bytes (incl '=') into 1-3 bytes

			int i = 0;

			for (int j = 0; sIx <= eIx - pad; j++)

				i |= IA[sArr[sIx++]] << (18 - j * 6);

			for (int r = 16; d < len; r -= 8)

				dArr[d++] = (byte) (i >> r);

		}

		return dArr;

	}

	// ****************************************************************************************

	// * byte[] version

	// ****************************************************************************************

	public final static byte[] encodeToByte(byte[] sArr) {

		return encodeToByte(sArr, devLineSep);

	}

	/**
	 * 
	 * Encodes a raw byte array into a BASE64 <code>byte[]</code>
	 * 
	 * representation i accordance with RFC 2045.
	 * 
	 * 
	 * 
	 * @param sArr
	 * 
	 * The bytes to convert. If <code>null</code> or length 0 an
	 * 
	 * empty array will be returned.
	 * 
	 * @param lineSep
	 * 
	 * Optional "\r\n" after 76 characters, unless end of file.<br>
	 * 
	 * No line separator will be in breach of RFC 2045 which
	 * 
	 * specifies max 76 per line but will be a little faster.
	 * 
	 * @return A BASE64 encoded array. Never <code>null</code>.
	 * 
	 */

	public final static byte[] encodeToByte(byte[] sArr, boolean lineSep) {

		// Check special case

		int sLen = sArr != null ? sArr.length : 0;

		if (sLen == 0)

			return new byte[0];

		int eLen = (sLen / 3) * 3; // Length of even 24-bits.

		int cCnt = ((sLen - 1) / 3 + 1) << 2; // Returned character count

		int dLen = cCnt + (lineSep ? (cCnt - 1) / 76 << 1 : 0); // Length of

		// returned

		// array

		byte[] dArr = new byte[dLen];

		// Encode even 24-bits

		for (int s = 0, d = 0, cc = 0; s < eLen;) {

			// Copy next three bytes into lower 24 bits of int, paying attension

			// to sign.

			int i = (sArr[s++] & 0xff) << 16 | (sArr[s++] & 0xff) << 8

			| (sArr[s++] & 0xff);

			// Encode the int into four chars

			dArr[d++] = (byte) CA[(i >>> 18) & 0x3f];

			dArr[d++] = (byte) CA[(i >>> 12) & 0x3f];

			dArr[d++] = (byte) CA[(i >>> 6) & 0x3f];

			dArr[d++] = (byte) CA[i & 0x3f];

			// Add optional line separator

			if (lineSep && ++cc == 19 && d < dLen - 2) {

				dArr[d++] = '\r';

				dArr[d++] = '\n';

				cc = 0;

			}

		}

		// Pad and encode last bits if source isn't an even 24 bits.

		int left = sLen - eLen; // 0 - 2.

		if (left > 0) {

			// Prepare the int

			int i = ((sArr[eLen] & 0xff) << 10)

			| (left == 2 ? ((sArr[sLen - 1] & 0xff) << 2) : 0);

			// Set last four chars

			dArr[dLen - 4] = (byte) CA[i >> 12];

			dArr[dLen - 3] = (byte) CA[(i >>> 6) & 0x3f];

			dArr[dLen - 2] = left == 2 ? (byte) CA[i & 0x3f] : (byte) '=';

			dArr[dLen - 1] = '=';

		}

		return dArr;

	}

	/**
	 * 
	 * Decodes a BASE64 encoded byte array. All illegal characters will be
	 * 
	 * ignored and can handle both arrays with and without line separators.
	 * 
	 * 
	 * 
	 * @param sArr
	 * 
	 * The source array. Length 0 will return an empty array.
	 * 
	 * <code>null</code> will throw an exception.
	 * 
	 * @return The decoded array of bytes. May be of length 0. Will be
	 * 
	 * <code>null</code> if the legal characters (including '=') isn't
	 * 
	 * divideable by 4. (I.e. definitely corrupted).
	 * 
	 */

	public final static byte[] decode(byte[] sArr) {

		// Check special case

		int sLen = sArr.length;

		// Count illegal characters (including '\r', '\n') to know what size the

		// returned array will be,

		// so we don't have to reallocate & copy it later.

		int sepCnt = 0; // Number of separator characters. (Actually illegal

		// characters, but that's a bonus...)

		for (int i = 0; i < sLen; i++)

			// If input is "pure" (I.e. no line separators or illegal chars)

			// base64 this loop can be commented out.

			if (IA[sArr[i] & 0xff] < 0)

				sepCnt++;

		// Check so that legal chars (including '=') are evenly divideable by 4

		// as specified in RFC 2045.

		if ((sLen - sepCnt) % 4 != 0)

			return null;

		int pad = 0;

		for (int i = sLen; i > 1 && IA[sArr[--i] & 0xff] <= 0;)

			if (sArr[i] == '=')

				pad++;

		int len = ((sLen - sepCnt) * 6 >> 3) - pad;

		byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

		for (int s = 0, d = 0; d < len;) {

			// Assemble three bytes into an int from four "valid" characters.

			int i = 0;

			for (int j = 0; j < 4; j++) { // j only increased if a valid char

				// was found.

				int c = IA[sArr[s++] & 0xff];

				if (c >= 0)

					i |= c << (18 - j * 6);

				else

					j--;

			}

			// Add the bytes

			dArr[d++] = (byte) (i >> 16);

			if (d < len) {

				dArr[d++] = (byte) (i >> 8);

				if (d < len)

					dArr[d++] = (byte) i;

			}

		}

		return dArr;

	}

	/**
	 * 
	 * Decodes a BASE64 encoded byte array that is known to be resonably well
	 * 
	 * formatted. The method is about twice as fast as {@link #decode(byte[])}.
	 * 
	 * The preconditions are:<br> + The array must have a line length of 76
	 * 
	 * chars OR no line separators at all (one line).<br> + Line separator must
	 * 
	 * be "\r\n", as specified in RFC 2045 + The array must not contain illegal
	 * 
	 * characters within the encoded string<br> + The array CAN have illegal
	 * 
	 * characters at the beginning and end, those will be dealt with
	 * 
	 * appropriately.<br>
	 * 
	 * 
	 * 
	 * @param sArr
	 * 
	 * The source array. Length 0 will return an empty array.
	 * 
	 * <code>null</code> will throw an exception.
	 * 
	 * @return The decoded array of bytes. May be of length 0.
	 * 
	 */

	public final static byte[] decodeFast(byte[] sArr) {

		// Check special case

		int sLen = sArr.length;

		if (sLen == 0)

			return new byte[0];

		int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.

		// Trim illegal chars from start

		while (sIx < eIx && IA[sArr[sIx] & 0xff] < 0)

			sIx++;

		// Trim illegal chars from end

		while (eIx > 0 && IA[sArr[eIx] & 0xff] < 0)

			eIx--;

		// get the padding count (=) (0, 1 or 2)

		int pad = sArr[eIx] == '=' ? (sArr[eIx - 1] == '=' ? 2 : 1) : 0; // Count

		// '='

		// at

		// end.

		int cCnt = eIx - sIx + 1; // Content count including possible

		// separators

		int sepCnt = sLen > 76 ? (sArr[76] == '\r' ? cCnt / 78 : 0) << 1 : 0;

		int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

		// bytes

		byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

		// Decode all but the last 0 - 2 bytes.

		int d = 0;

		for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

			// Assemble three bytes into an int from four "valid" characters.

			int i = IA[sArr[sIx++]] << 18 | IA[sArr[sIx++]] << 12

			| IA[sArr[sIx++]] << 6 | IA[sArr[sIx++]];

			// Add the bytes

			dArr[d++] = (byte) (i >> 16);

			dArr[d++] = (byte) (i >> 8);

			dArr[d++] = (byte) i;

			// If line separator, jump over it.

			if (sepCnt > 0 && ++cc == 19) {

				sIx += 2;

				cc = 0;

			}

		}

		if (d < len) {

			// Decode last 1-3 bytes (incl '=') into 1-3 bytes

			int i = 0;

			for (int j = 0; sIx <= eIx - pad; j++)

				i |= IA[sArr[sIx++]] << (18 - j * 6);

			for (int r = 16; d < len; r -= 8)

				dArr[d++] = (byte) (i >> r);

		}

		return dArr;

	}

	// ****************************************************************************************

	// * String version

	// ****************************************************************************************

	/**
	 * 
	 * Encodes a raw byte array into a BASE64 <code>String</code>
	 * 
	 * representation i accordance with RFC 2045.
	 * 
	 * 
	 * 
	 * @param sArr
	 * 
	 * The bytes to convert. If <code>null</code> or length 0 an
	 * 
	 * empty array will be returned.
	 * 
	 * @param lineSep
	 * 
	 * Optional "\r\n" after 76 characters, unless end of file.<br>
	 * 
	 * No line separator will be in breach of RFC 2045 which
	 * 
	 * specifies max 76 per line but will be a little faster.
	 * 
	 * @return A BASE64 encoded array. Never <code>null</code>.
	 * 
	 */

	public final static String encodeToString(byte[] sArr, boolean lineSep) {

		// Reuse char[] since we can't create a String incrementally anyway and

		// StringBuffer/Builder would be slower.

		return new String(encodeToChar(sArr, lineSep));

	}

	public final static String encodeToString(byte[] sArr) {

		// Reuse char[] since we can't create a String incrementally anyway and

		// StringBuffer/Builder would be slower.

		return new String(encodeToChar(sArr, devLineSep));

	}

	/**
	 * 
	 * Decodes a BASE64 encoded <code>String</code>. All illegal characters
	 * 
	 * will be ignored and can handle both strings with and without line
	 * 
	 * separators.<br>
	 * 
	 * <b>Note!</b> It can be up to about 2x the speed to call
	 * 
	 * <code>decode(str.toCharArray())</code> instead. That will create a
	 * 
	 * temporary array though. This version will use <code>str.charAt(i)</code>
	 * 
	 * to iterate the string.
	 * 
	 * 
	 * 
	 * @param str
	 * 
	 * The source string. <code>null</code> or length 0 will return
	 * 
	 * an empty array.
	 * 
	 * @return The decoded array of bytes. May be of length 0. Will be
	 * 
	 * <code>null</code> if the legal characters (including '=') isn't
	 * 
	 * divideable by 4. (I.e. definitely corrupted).
	 * 
	 */

	public final static byte[] decode(String str) {

		// Check special case

		int sLen = str != null ? str.length() : 0;

		if (sLen == 0)

			return new byte[0];

		// Count illegal characters (including '\r', '\n') to know what size the

		// returned array will be,

		// so we don't have to reallocate & copy it later.

		int sepCnt = 0; // Number of separator characters. (Actually illegal

		// characters, but that's a bonus...)

		for (int i = 0; i < sLen; i++)

			// If input is "pure" (I.e. no line separators or illegal chars)

			// base64 this loop can be commented out.

			if (IA[str.charAt(i)] < 0)

				sepCnt++;

		// Check so that legal chars (including '=') are evenly divideable by 4

		// as specified in RFC 2045.

		if ((sLen - sepCnt) % 4 != 0)

			return null;

		// Count '=' at end

		int pad = 0;

		for (int i = sLen; i > 1 && IA[str.charAt(--i)] <= 0;)

			if (str.charAt(i) == '=')

				pad++;

		int len = ((sLen - sepCnt) * 6 >> 3) - pad;

		byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

		for (int s = 0, d = 0; d < len;) {

			// Assemble three bytes into an int from four "valid" characters.

			int i = 0;

			for (int j = 0; j < 4; j++) { // j only increased if a valid char

				// was found.

				int c = IA[str.charAt(s++)];

				if (c >= 0)

					i |= c << (18 - j * 6);

				else

					j--;

			}

			// Add the bytes

			dArr[d++] = (byte) (i >> 16);

			if (d < len) {

				dArr[d++] = (byte) (i >> 8);

				if (d < len)

					dArr[d++] = (byte) i;

			}

		}

		return dArr;

	}

	/**
	 * 
	 * Decodes a BASE64 encoded string that is known to be resonably well
	 * 
	 * formatted. The method is about twice as fast as {@link #decode(String)}.
	 * 
	 * The preconditions are:<br> + The array must have a line length of 76
	 * 
	 * chars OR no line separators at all (one line).<br> + Line separator must
	 * 
	 * be "\r\n", as specified in RFC 2045 + The array must not contain illegal
	 * 
	 * characters within the encoded string<br> + The array CAN have illegal
	 * 
	 * characters at the beginning and end, those will be dealt with
	 * 
	 * appropriately.<br>
	 * 
	 * 
	 * 
	 * @param s
	 * 
	 * The source string. Length 0 will return an empty array.
	 * 
	 * <code>null</code> will throw an exception.
	 * 
	 * @return The decoded array of bytes. May be of length 0.
	 * 
	 */

	public final static byte[] decodeFast(String s) {

		// Check special case

		int sLen = s.length();

		if (sLen == 0)

			return new byte[0];

		int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.

		// Trim illegal chars from start

		while (sIx < eIx && IA[s.charAt(sIx) & 0xff] < 0)

			sIx++;

		// Trim illegal chars from end

		while (eIx > 0 && IA[s.charAt(eIx) & 0xff] < 0)

			eIx--;

		// get the padding count (=) (0, 1 or 2)

		int pad = s.charAt(eIx) == '=' ? (s.charAt(eIx - 1) == '=' ? 2 : 1) : 0; // Count

		// '='

		// at

		// end.

		int cCnt = eIx - sIx + 1; // Content count including possible

		// separators

		int sepCnt = sLen > 76 ? (s.charAt(76) == '\r' ? cCnt / 78 : 0) << 1

		: 0;

		int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

		// bytes

		byte[] dArr = new byte[len]; // Preallocate byte[] of exact length

		// Decode all but the last 0 - 2 bytes.

		int d = 0;

		for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

			// Assemble three bytes into an int from four "valid" characters.

			int i = IA[s.charAt(sIx++)] << 18 | IA[s.charAt(sIx++)] << 12

			| IA[s.charAt(sIx++)] << 6 | IA[s.charAt(sIx++)];

			// Add the bytes

			dArr[d++] = (byte) (i >> 16);

			dArr[d++] = (byte) (i >> 8);

			dArr[d++] = (byte) i;

			// If line separator, jump over it.

			if (sepCnt > 0 && ++cc == 19) {

				sIx += 2;

				cc = 0;

			}

		}

		if (d < len) {

			// Decode last 1-3 bytes (incl '=') into 1-3 bytes

			int i = 0;

			for (int j = 0; sIx <= eIx - pad; j++)

				i |= IA[s.charAt(sIx++)] << (18 - j * 6);

			for (int r = 16; d < len; r -= 8)

				dArr[d++] = (byte) (i >> r);

		}

		return dArr;

	}

//
//	public static void main(String[] args){
//		String base64 = "";
////		try {
////			InputStream in = new FileInputStream(new File("/Users/steven.j/Desktop/in.txt"));
////			byte[] bytes1 = new byte[4096];
////			while(in.read(bytes1)!=-1){
////				base64 += new String(bytes1);
////			}
////		} catch (FileNotFoundException e) {
////			e.printStackTrace();
////		} catch (IOException e) {
////			e.printStackTrace();
////		}
//
////		try {
////			base64 = Base64.encodeToString(FileUtils.readFileToByteArray(new File("/Users/steven.j/Desktop/1111.pdf")));
////		} catch (IOException e) {
////			e.printStackTrace();
////		}
//
//		try {
//		    InputStream in = new FileInputStream(new File("/Users/steven.j/Desktop/2222.pdf"));
//			base64 = Base64.encodeToString(IOUtils.toByteArray(in));
////			base64 = FileUtils.readFileToString(new File("/Users/steven.j/Desktop/in.txt"), Charset.forName("UTF-8"));
//		} catch (IOException e) {
//			e.printStackTrace();
//		}
//
//
//		byte[] bytes = Base64.decode(base64);
//		try {
//			OutputStream outputStream = new FileOutputStream(new File("/Users/steven.j/Desktop/out.pdf"));
//			outputStream.write(bytes);
//		} catch (FileNotFoundException e) {
//			e.printStackTrace();
//		} catch (IOException e) {
//			e.printStackTrace();
//		}
//
//	}

}